PPC: Altivec split-radix FFT

1.8x faster than altivec radix-2 on a G4
8% faster vorbis decoding

Patch (mostly) by Loren Merritt

Originally committed as revision 23956 to svn://svn.ffmpeg.org/ffmpeg/trunk

4 files changed, 396 insertions, 98 deletions

diff --git a/libavcodec/ppc/Makefile b/libavcodec/ppc/Makefile
index 3bbd6c3630..175b1093b0 100644
--- a/libavcodec/ppc/Makefile
+++ b/libavcodec/ppc/Makefile
@@ -13,10 +13,14 @@ ALTIVEC-OBJS-$(CONFIG_MP3FLOAT_DECODER)    += ppc/mpegaudiodec_altivec.o
 ALTIVEC-OBJS-$(CONFIG_MP3ON4FLOAT_DECODER) += ppc/mpegaudiodec_altivec.o
 ALTIVEC-OBJS-$(CONFIG_MP3ADUFLOAT_DECODER) += ppc/mpegaudiodec_altivec.o
 
+FFT-OBJS-$(HAVE_GNU_AS)                += ppc/fft_altivec_s.o           \
+
+ALTIVEC-OBJS-$(CONFIG_FFT)             += ppc/fft_altivec.o             \
+                                          $(FFT-OBJS-yes)
+
 OBJS-$(HAVE_ALTIVEC)                   += ppc/check_altivec.o           \
                                           ppc/dsputil_altivec.o         \
                                           ppc/fdct_altivec.o            \
-                                          ppc/fft_altivec.o             \
                                           ppc/float_altivec.o           \
                                           ppc/gmc_altivec.o             \
                                           ppc/idct_altivec.o            \
diff --git a/libavcodec/ppc/fft_altivec.c b/libavcodec/ppc/fft_altivec.c
index 5ef3bd3559..3f622c3aba 100644
--- a/libavcodec/ppc/fft_altivec.c
+++ b/libavcodec/ppc/fft_altivec.c
@@ -1,8 +1,7 @@
 /*
  * FFT/IFFT transforms
  * AltiVec-enabled
- * Copyright (c) 2003 Romain Dolbeau <romain@dolbeau.org>
- * Based on code Copyright (c) 2002 Fabrice Bellard
+ * Copyright (c) 2009 Loren Merritt
  *
  * This file is part of FFmpeg.
  *
@@ -22,7 +21,8 @@
  */
 #include "libavcodec/fft.h"
 #include "util_altivec.h"
-#include "dsputil_altivec.h"
+#include "types_altivec.h"
+#include "regs.h"
 
 /**
  * Do a complex FFT with the parameters defined in ff_fft_init(). The
@@ -31,107 +31,65 @@
  * AltiVec-enabled
  * This code assumes that the 'z' pointer is 16 bytes-aligned
  * It also assumes all FFTComplex are 8 bytes-aligned pair of float
- * The code is exactly the same as the SSE version, except
- * that successive MUL + ADD/SUB have been merged into
- * fused multiply-add ('vec_madd' in altivec)
  */
-static void ff_fft_calc_altivec(FFTContext *s, FFTComplex *z)
-{
-    register const vector float vczero = (const vector float)vec_splat_u32(0.);
-
-    int ln = s->nbits;
-    int j, np, np2;
-    int nblocks, nloops;
-    register FFTComplex *p, *q;
-    FFTComplex *cptr, *cptr1;
-    int k;
-
-    np = 1 << ln;
-
-    {
-        vector float *r, a, b, a1, c1, c2;
-
-        r = (vector float *)&z[0];
-
-        c1 = vcii(p,p,n,n);
-
-        if (s->inverse) {
-            c2 = vcii(p,p,n,p);
-        } else {
-            c2 = vcii(p,p,p,n);
-        }
-
-        j = (np >> 2);
-        do {
-            a = vec_ld(0, r);
-            a1 = vec_ld(sizeof(vector float), r);
-
-            b = vec_perm(a,a,vcprmle(1,0,3,2));
-            a = vec_madd(a,c1,b);
-            /* do the pass 0 butterfly */
-
-            b = vec_perm(a1,a1,vcprmle(1,0,3,2));
-            b = vec_madd(a1,c1,b);
-            /* do the pass 0 butterfly */
 
-            /* multiply third by -i */
-            b = vec_perm(b,b,vcprmle(2,3,1,0));
+// Pointers to functions. Not using function pointer syntax, because
+// that involves an extra level of indirection on some PPC ABIs.
+extern void *ff_fft_dispatch_altivec[2][15];
 
-            /* do the pass 1 butterfly */
-            vec_st(vec_madd(b,c2,a), 0, r);
-            vec_st(vec_nmsub(b,c2,a), sizeof(vector float), r);
-
-            r += 2;
-        } while (--j != 0);
+// Convert from simd order to C order.
+static void swizzle(vec_f *z, int n)
+{
+    int i;
+    n >>= 1;
+    for (i = 0; i < n; i += 2) {
+        vec_f re = z[i];
+        vec_f im = z[i+1];
+        z[i]   = vec_mergeh(re, im);
+        z[i+1] = vec_mergel(re, im);
     }
-    /* pass 2 .. ln-1 */
-
-    nblocks = np >> 3;
-    nloops = 1 << 2;
-    np2 = np >> 1;
-
-    cptr1 = s->exptab1;
-    do {
-        p = z;
-        q = z + nloops;
-        j = nblocks;
-        do {
-            cptr = cptr1;
-            k = nloops >> 1;
-            do {
-                vector float a,b,c,t1;
-
-                a = vec_ld(0, (float*)p);
-                b = vec_ld(0, (float*)q);
-
-                /* complex mul */
-                c = vec_ld(0, (float*)cptr);
-                /*  cre*re cim*re */
-                t1 = vec_madd(c, vec_perm(b,b,vcprmle(2,2,0,0)),vczero);
-                c = vec_ld(sizeof(vector float), (float*)cptr);
-                /*  -cim*im cre*im */
-                b = vec_madd(c, vec_perm(b,b,vcprmle(3,3,1,1)),t1);
-
-                /* butterfly */
-                vec_st(vec_add(a,b), 0, (float*)p);
-                vec_st(vec_sub(a,b), 0, (float*)q);
-
-                p += 2;
-                q += 2;
-                cptr += 4;
-            } while (--k);
+}
 
-            p += nloops;
-            q += nloops;
-        } while (--j);
-        cptr1 += nloops * 2;
-        nblocks = nblocks >> 1;
-        nloops = nloops << 1;
-    } while (nblocks != 0);
+static void ff_fft_calc_altivec(FFTContext *s, FFTComplex *z)
+{
+    register vec_f  v14 __asm__("v14") = {0,0,0,0};
+    register vec_f  v15 __asm__("v15") = *(const vec_f*)ff_cos_16;
+    register vec_f  v16 __asm__("v16") = {0, 0.38268343, M_SQRT1_2, 0.92387953};
+    register vec_f  v17 __asm__("v17") = {-M_SQRT1_2, M_SQRT1_2, M_SQRT1_2,-M_SQRT1_2};
+    register vec_f  v18 __asm__("v18") = { M_SQRT1_2, M_SQRT1_2, M_SQRT1_2, M_SQRT1_2};
+    register vec_u8 v19 __asm__("v19") = vcprm(s0,3,2,1);
+    register vec_u8 v20 __asm__("v20") = vcprm(0,1,s2,s1);
+    register vec_u8 v21 __asm__("v21") = vcprm(2,3,s0,s3);
+    register vec_u8 v22 __asm__("v22") = vcprm(2,s3,3,s2);
+    register vec_u8 v23 __asm__("v23") = vcprm(0,1,s0,s1);
+    register vec_u8 v24 __asm__("v24") = vcprm(2,3,s2,s3);
+    register vec_u8 v25 __asm__("v25") = vcprm(2,3,0,1);
+    register vec_u8 v26 __asm__("v26") = vcprm(1,2,s3,s0);
+    register vec_u8 v27 __asm__("v27") = vcprm(0,3,s2,s1);
+    register vec_u8 v28 __asm__("v28") = vcprm(0,2,s1,s3);
+    register vec_u8 v29 __asm__("v29") = vcprm(1,3,s0,s2);
+    register FFTSample *const*cos_tabs __asm__("r12") = ff_cos_tabs;
+    register FFTComplex *zarg __asm__("r3") = z;
+    __asm__(
+        "mtctr %0               \n"
+        "li   "r(9)", 16        \n"
+        "subi "r(1)","r(1) ",%1 \n"
+        "bctrl                  \n"
+        "addi "r(1)","r(1) ",%1 \n"
+        ::"r"(ff_fft_dispatch_altivec[1][s->nbits-2]), "i"(12*sizeof(void*)),
+          "r"(zarg), "r"(cos_tabs),
+          "v"(v14),"v"(v15),"v"(v16),"v"(v17),"v"(v18),"v"(v19),"v"(v20),"v"(v21),
+          "v"(v22),"v"(v23),"v"(v24),"v"(v25),"v"(v26),"v"(v27),"v"(v28),"v"(v29)
+        : "lr","ctr","r0","r4","r5","r6","r7","r8","r9","r10","r11",
+          "v0","v1","v2","v3","v4","v5","v6","v7","v8","v9","v10","v11","v12","v13"
+    );
+    if (s->nbits <= 4)
+        swizzle((vec_f*)z, 1<<s->nbits);
 }
 
 av_cold void ff_fft_init_altivec(FFTContext *s)
 {
-    s->fft_calc = ff_fft_calc_altivec;
-    s->split_radix = 0;
+    if (HAVE_GNU_AS)
+        s->fft_calc = ff_fft_calc_altivec;
+    s->split_radix = 1;
 }
diff --git a/libavcodec/ppc/fft_altivec_s.S b/libavcodec/ppc/fft_altivec_s.S
new file mode 100644
index 0000000000..ed7b045e40
--- /dev/null
+++ b/libavcodec/ppc/fft_altivec_s.S
@@ -0,0 +1,335 @@
+/*
+ * FFT transform with Altivec optimizations
+ * Copyright (c) 2009 Loren Merritt
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/*
+ * These functions are not individually interchangeable with the C versions.
+ * While C takes arrays of FFTComplex, Altivec leaves intermediate results
+ * in blocks as convenient to the vector size.
+ * i.e. {4x real, 4x imaginary, 4x real, ...}
+ *
+ * I ignore standard calling convention.
+ * Instead, the following registers are treated as global constants:
+ * v14: zero
+ * v15..v18: cosines
+ * v19..v29: permutations
+ * r9: 16
+ * r12: ff_cos_tabs
+ * and the rest are free for local use.
+ */
+
+#include "config.h"
+#include "asm.S"
+
+.text
+
+/* Apple gas doesn't support this shorthand */
+.macro mtctr rx
+    mtspr 9, \rx
+.endm
+
+.macro addi2 ra, imm // add 32-bit immediate
+.if \imm & 0xffff
+    addi \ra, \ra, \imm@l
+.endif
+.if (\imm+0x8000)>>16
+    addis \ra, \ra, \imm@ha
+.endif
+.endm
+
+#if ARCH_PPC64
+#define PTR .quad
+.macro LOAD_PTR ra, rbase, offset
+    ld  \ra,(\offset)*8(\rbase)
+.endm
+.macro STORE_PTR ra, rbase, offset
+    std \ra,(\offset)*8(\rbase)
+.endm
+#else
+#define PTR .int
+.macro LOAD_PTR ra, rbase, offset
+    lwz \ra,(\offset)*4(\rbase)
+.endm
+.macro STORE_PTR ra, rbase, offset
+    stw \ra,(\offset)*4(\rbase)
+.endm
+#endif
+
+.macro FFT4 a0, a1, a2, a3 // in:0-1 out:2-3
+    vperm   \a2,\a0,\a1,v20 // vcprm(0,1,s2,s1) // {r0,i0,r3,i2}
+    vperm   \a3,\a0,\a1,v21 // vcprm(2,3,s0,s3) // {r1,i1,r2,i3}
+    vaddfp  \a0,\a2,\a3                         // {t1,t2,t6,t5}
+    vsubfp  \a1,\a2,\a3                         // {t3,t4,t8,t7}
+    vmrghw  \a2,\a0,\a1     // vcprm(0,s0,1,s1) // {t1,t3,t2,t4}
+    vperm   \a3,\a0,\a1,v22 // vcprm(2,s3,3,s2) // {t6,t7,t5,t8}
+    vaddfp  \a0,\a2,\a3                         // {r0,r1,i0,i1}
+    vsubfp  \a1,\a2,\a3                         // {r2,r3,i2,i3}
+    vperm   \a2,\a0,\a1,v23 // vcprm(0,1,s0,s1) // {r0,r1,r2,r3}
+    vperm   \a3,\a0,\a1,v24 // vcprm(2,3,s2,s3) // {i0,i1,i2,i3}
+.endm
+
+.macro FFT4x2 a0, a1, b0, b1, a2, a3, b2, b3
+    vperm   \a2,\a0,\a1,v20 // vcprm(0,1,s2,s1) // {r0,i0,r3,i2}
+    vperm   \a3,\a0,\a1,v21 // vcprm(2,3,s0,s3) // {r1,i1,r2,i3}
+    vperm   \b2,\b0,\b1,v20
+    vperm   \b3,\b0,\b1,v21
+    vaddfp  \a0,\a2,\a3                         // {t1,t2,t6,t5}
+    vsubfp  \a1,\a2,\a3                         // {t3,t4,t8,t7}
+    vaddfp  \b0,\b2,\b3
+    vsubfp  \b1,\b2,\b3
+    vmrghw  \a2,\a0,\a1     // vcprm(0,s0,1,s1) // {t1,t3,t2,t4}
+    vperm   \a3,\a0,\a1,v22 // vcprm(2,s3,3,s2) // {t6,t7,t5,t8}
+    vmrghw  \b2,\b0,\b1
+    vperm   \b3,\b0,\b1,v22
+    vaddfp  \a0,\a2,\a3                         // {r0,r1,i0,i1}
+    vsubfp  \a1,\a2,\a3                         // {r2,r3,i2,i3}
+    vaddfp  \b0,\b2,\b3
+    vsubfp  \b1,\b2,\b3
+    vperm   \a2,\a0,\a1,v23 // vcprm(0,1,s0,s1) // {r0,r1,r2,r3}
+    vperm   \a3,\a0,\a1,v24 // vcprm(2,3,s2,s3) // {i0,i1,i2,i3}
+    vperm   \b2,\b0,\b1,v23
+    vperm   \b3,\b0,\b1,v24
+.endm
+
+.macro FFT8 a0, a1, b0, b1, a2, a3, b2, b3, b4 // in,out:a0-b1
+    vmrghw  \b2,\b0,\b1     // vcprm(0,s0,1,s1) // {r4,r6,i4,i6}
+    vmrglw  \b3,\b0,\b1     // vcprm(2,s2,3,s3) // {r5,r7,i5,i7}
+    vperm   \a2,\a0,\a1,v20         // FFT4 ...
+    vperm   \a3,\a0,\a1,v21
+    vaddfp  \b0,\b2,\b3                         // {t1,t3,t2,t4}
+    vsubfp  \b1,\b2,\b3                         // {r5,r7,i5,i7}
+    vperm   \b4,\b1,\b1,v25 // vcprm(2,3,0,1)   // {i5,i7,r5,r7}
+    vaddfp  \a0,\a2,\a3
+    vsubfp  \a1,\a2,\a3
+    vmaddfp \b1,\b1,v17,v14 // * {-1,1,1,-1}/sqrt(2)
+    vmaddfp \b1,\b4,v18,\b1 // * { 1,1,1,1 }/sqrt(2) // {t8,ta,t7,t9}
+    vmrghw  \a2,\a0,\a1
+    vperm   \a3,\a0,\a1,v22
+    vperm   \b2,\b0,\b1,v26 // vcprm(1,2,s3,s0) // {t3,t2,t9,t8}
+    vperm   \b3,\b0,\b1,v27 // vcprm(0,3,s2,s1) // {t1,t4,t7,ta}
+    vaddfp  \a0,\a2,\a3
+    vsubfp  \a1,\a2,\a3
+    vaddfp  \b0,\b2,\b3                         // {t1,t2,t9,ta}
+    vsubfp  \b1,\b2,\b3                         // {t6,t5,tc,tb}
+    vperm   \a2,\a0,\a1,v23
+    vperm   \a3,\a0,\a1,v24
+    vperm   \b2,\b0,\b1,v28 // vcprm(0,2,s1,s3) // {t1,t9,t5,tb}
+    vperm   \b3,\b0,\b1,v29 // vcprm(1,3,s0,s2) // {t2,ta,t6,tc}
+    vsubfp  \b0,\a2,\b2                         // {r4,r5,r6,r7}
+    vsubfp  \b1,\a3,\b3                         // {i4,i5,i6,i7}
+    vaddfp  \a0,\a2,\b2                         // {r0,r1,r2,r3}
+    vaddfp  \a1,\a3,\b3                         // {i0,i1,i2,i3}
+.endm
+
+.macro BF d0,d1,s0,s1
+    vsubfp  \d1,\s0,\s1
+    vaddfp  \d0,\s0,\s1
+.endm
+
+fft4_altivec:
+    lvx    v0, 0,r3
+    lvx    v1,r9,r3
+    FFT4   v0,v1,v2,v3
+    stvx   v2, 0,r3
+    stvx   v3,r9,r3
+    blr
+
+fft8_altivec:
+    addi   r4,r3,32
+    lvx    v0, 0,r3
+    lvx    v1,r9,r3
+    lvx    v2, 0,r4
+    lvx    v3,r9,r4
+    FFT8   v0,v1,v2,v3,v4,v5,v6,v7,v8
+    stvx   v0, 0,r3
+    stvx   v1,r9,r3
+    stvx   v2, 0,r4
+    stvx   v3,r9,r4
+    blr
+
+fft16_altivec:
+    addi   r5,r3,64
+    addi   r6,r3,96
+    addi   r4,r3,32
+    lvx    v0, 0,r5
+    lvx    v1,r9,r5
+    lvx    v2, 0,r6
+    lvx    v3,r9,r6
+    FFT4x2 v0,v1,v2,v3,v4,v5,v6,v7
+    lvx    v0, 0,r3
+    lvx    v1,r9,r3
+    lvx    v2, 0,r4
+    lvx    v3,r9,r4
+    FFT8   v0,v1,v2,v3,v8,v9,v10,v11,v12
+    vmaddfp   v8,v4,v15,v14 // r2*wre
+    vmaddfp   v9,v5,v15,v14 // i2*wre
+    vmaddfp  v10,v6,v15,v14 // r3*wre
+    vmaddfp  v11,v7,v15,v14 // i3*wre
+    vmaddfp   v8,v5,v16,v8  // i2*wim
+    vnmsubfp  v9,v4,v16,v9  // r2*wim
+    vnmsubfp v10,v7,v16,v10 // i3*wim
+    vmaddfp  v11,v6,v16,v11 // r3*wim
+    BF     v10,v12,v10,v8
+    BF     v11,v13,v9,v11
+    BF     v0,v4,v0,v10
+    BF     v3,v7,v3,v12
+    stvx   v0, 0,r3
+    stvx   v4, 0,r5
+    stvx   v3,r9,r4
+    stvx   v7,r9,r6
+    BF     v1,v5,v1,v11
+    BF     v2,v6,v2,v13
+    stvx   v1,r9,r3
+    stvx   v5,r9,r5
+    stvx   v2, 0,r4
+    stvx   v6, 0,r6
+    blr
+
+// void pass(float *z, float *wre, int n)
+.macro PASS interleave, suffix
+fft_pass\suffix\()_altivec:
+    mtctr  r5
+    slwi   r0,r5,4
+    slwi   r7,r5,6   // o2
+    slwi   r5,r5,5   // o1
+    add   r10,r5,r7  // o3
+    add    r0,r4,r0  // wim
+    addi   r6,r5,16  // o1+16
+    addi   r8,r7,16  // o2+16
+    addi  r11,r10,16 // o3+16
+1:
+    lvx    v8, 0,r4  // wre
+    lvx   v10, 0,r0  // wim
+    sub    r0,r0,r9
+    lvx    v9, 0,r0
+    vperm  v9,v9,v10,v19   // vcprm(s0,3,2,1) => wim[0 .. -3]
+    lvx    v4,r3,r7        // r2 = z[o2]
+    lvx    v5,r3,r8        // i2 = z[o2+16]
+    lvx    v6,r3,r10       // r3 = z[o3]
+    lvx    v7,r3,r11       // i3 = z[o3+16]
+    vmaddfp  v10,v4,v8,v14 // r2*wre
+    vmaddfp  v11,v5,v8,v14 // i2*wre
+    vmaddfp  v12,v6,v8,v14 // r3*wre
+    vmaddfp  v13,v7,v8,v14 // i3*wre
+    lvx    v0, 0,r3        // r0 = z[0]
+    lvx    v3,r3,r6        // i1 = z[o1+16]
+    vmaddfp  v10,v5,v9,v10 // i2*wim
+    vnmsubfp v11,v4,v9,v11 // r2*wim
+    vnmsubfp v12,v7,v9,v12 // i3*wim
+    vmaddfp  v13,v6,v9,v13 // r3*wim
+    lvx    v1,r3,r9        // i0 = z[16]
+    lvx    v2,r3,r5        // r1 = z[o1]
+    BF     v12,v8,v12,v10
+    BF     v13,v9,v11,v13
+    BF     v0,v4,v0,v12
+    BF     v3,v7,v3,v8
+.if !\interleave
+    stvx   v0, 0,r3
+    stvx   v4,r3,r7
+    stvx   v3,r3,r6
+    stvx   v7,r3,r11
+.endif
+    BF     v1,v5,v1,v13
+    BF     v2,v6,v2,v9
+.if !\interleave
+    stvx   v1,r3,r9
+    stvx   v2,r3,r5
+    stvx   v5,r3,r8
+    stvx   v6,r3,r10
+.else
+    vmrghw v8,v0,v1
+    vmrglw v9,v0,v1
+    stvx   v8, 0,r3
+    stvx   v9,r3,r9
+    vmrghw v8,v2,v3
+    vmrglw v9,v2,v3
+    stvx   v8,r3,r5
+    stvx   v9,r3,r6
+    vmrghw v8,v4,v5
+    vmrglw v9,v4,v5
+    stvx   v8,r3,r7
+    stvx   v9,r3,r8
+    vmrghw v8,v6,v7
+    vmrglw v9,v6,v7
+    stvx   v8,r3,r10
+    stvx   v9,r3,r11
+.endif
+    addi   r3,r3,32
+    addi   r4,r4,16
+    bdnz 1b
+    sub    r3,r3,r5
+    blr
+.endm
+
+.macro DECL_FFT suffix, bits, n, n2, n4
+fft\n\suffix\()_altivec:
+    mflr  r0
+    STORE_PTR r0,r1,\bits-5
+    bl    fft\n2\()_altivec
+    addi2 r3,\n*4
+    bl    fft\n4\()_altivec
+    addi2 r3,\n*2
+    bl    fft\n4\()_altivec
+    addi2 r3,\n*-6
+    LOAD_PTR r0,r1,\bits-5
+    LOAD_PTR r4,r12,\bits
+    mtlr  r0
+    li    r5,\n/16
+    b     fft_pass\suffix\()_altivec
+.endm
+
+.macro DECL_FFTS interleave, suffix
+    .text
+    PASS \interleave, \suffix
+    DECL_FFT \suffix, 5,   32,   16,    8
+    DECL_FFT \suffix, 6,   64,   32,   16
+    DECL_FFT \suffix, 7,  128,   64,   32
+    DECL_FFT \suffix, 8,  256,  128,   64
+    DECL_FFT \suffix, 9,  512,  256,  128
+    DECL_FFT \suffix,10, 1024,  512,  256
+    DECL_FFT \suffix,11, 2048, 1024,  512
+    DECL_FFT \suffix,12, 4096, 2048, 1024
+    DECL_FFT \suffix,13, 8192, 4096, 2048
+    DECL_FFT \suffix,14,16384, 8192, 4096
+    DECL_FFT \suffix,15,32768,16384, 8192
+    DECL_FFT \suffix,16,65536,32768,16384
+
+    .rodata
+    .global EXTERN_ASM\()ff_fft_dispatch\suffix\()_altivec
+EXTERN_ASM\()ff_fft_dispatch\suffix\()_altivec:
+    PTR fft4_altivec
+    PTR fft8_altivec
+    PTR fft16_altivec
+    PTR fft32\suffix\()_altivec
+    PTR fft64\suffix\()_altivec
+    PTR fft128\suffix\()_altivec
+    PTR fft256\suffix\()_altivec
+    PTR fft512\suffix\()_altivec
+    PTR fft1024\suffix\()_altivec
+    PTR fft2048\suffix\()_altivec
+    PTR fft4096\suffix\()_altivec
+    PTR fft8192\suffix\()_altivec
+    PTR fft16384\suffix\()_altivec
+    PTR fft32768\suffix\()_altivec
+    PTR fft65536\suffix\()_altivec
+.endm
+
+DECL_FFTS 0
+DECL_FFTS 1, _interleave
diff --git a/libavcodec/ppc/types_altivec.h b/libavcodec/ppc/types_altivec.h
index 2870e83e7a..36b6e1f388 100644
--- a/libavcodec/ppc/types_altivec.h
+++ b/libavcodec/ppc/types_altivec.h
@@ -30,6 +30,7 @@
 #define vec_s16 vector signed short
 #define vec_u32 vector unsigned int
 #define vec_s32 vector signed int
+#define vec_f   vector float
 
 /***********************************************************************
  * Null vector